Reversible-flow dry kiln



July 19, 1927, l 1,636,490

I R A SIMMONS REVERSBLE FLOW DRY KILN letentefd July i9, 1927.

' n. A. siiitiiroirs,l or `vnniroiriii, omieoifr;`

- REvERsIBLE-.rLov/innyKILN. y

Application inea Juiy 13, ieaaf, seriaiLimAaavi.

Thek object of my invention is to provide air circulating and conditioning-the latter referring to temperature Aand moisture-.-V means economically operated.

Torecirculate air which has become eXcesf sively laden with moisture absorbed .fromy teriorl air and iii that way displacing ther saturatedair. Butthe. means necessarily employed for suoli purpose greatly increase the cost of operation.. i f

lt has long beenl desired to .provide ei'iicient air circulation in the kkilnby means relatively simple Yandinexpensive to operate. I have discovered that this result `may be attained byv inducing a low v pressure vacuuin within the kilnthrough-the medium of va stack, and associatingpl-wi-th the air-inlet of the kiln means functioning both to condition the air-as to temperature and moistureandinducing its mov-ement. I attained this result by associating with the zair inlets heating coils and steam `sprays which inA coopera tion withthe low vacuumv induced byy the stacks cause the efficient circulation ofthe air in thekiln. Andfby providing two groups of said agenciesone at the middle of the kiln. under the pile oflumber, andthe others at thesides, and in conjunction therewith means for controlling each groupfof inlets,

and airconditioning and moying means as a unit-ftlie direction of air circulation within the kiln may be controlled.

The details of construction and mode ofV operation of my invention are hereinafter described with reference to the .accompany ing drawings, in which t Fig. 1 is a foreshorteiied plan section through a dry kiln embodying my invention with some portions being vshown* as broken away to disclose details of construction;

Fig. 2 is a diagrammatic vertical section through my` improved dry kiln showing the arrangement of the devices relatively to each other and the path of the circulated iiuids through the lkiln in one direction; and

Fig. 3 is a. similar section with the devices Aarranged to reverse the path of the circulation, the arrows in said igures indicating the reversed iiow through the kiln.

My improved kiln a is provided with doors (Hat one endtliroulgh' which thecar b carrying the loosely stacked/lumber 0 may be admitted, said car 1preferably running on tracks d extending,longitudinally ofthe kiln. Said tracksare supported by spaced stringersle which thus constitute a skeleton floor and beneath said .stringere the air inlet pipes f, ff and g are mounted. ,Perforated steam pipes L', L and z'. are preferably carried di` rectly on saidair inletnconduits j', f and g, respectively. The perforations are arranged as diagrammatically rillustrated 'in' Figs.. 2. ands so as to emit .jets of steainfzveivtically..Y

,The slittedfperforationsf2, fiend g infth'e air conduits f and g, respectively, areV Valso, arranged `at A,they top ofthe respective conduits, as `shown in Figl', solas to `direct jets of airupwardly, vertically. Arranged in vertical.alinenient with said conduits f, f" and g are heating coilsy', jfand k, respec- `tively, which, are heated by steam being.,

passed therethrough. `Said-'pipes are imperforate and are merely used to heat the yair emitted from the conduits, ffand g by.'r

the .heatwvhich is radiated through their walls. A Batlies Z' are arranged to separatethe side air,V conduits l f, and f', and the ,correspending-heating coils -j andV y, from the central aijr .conduit g and the central yheatingcoils-lc. l Said battles `extend downwardlyto' l poi-ntbelovwthe slitted perforations in said air conduits, and ii-ai'eoutwardly at their tops, as -shownin Figs. 2 and 3,-so-as to direct the vflow of air from the middle'conduit g across the entire stack of lumber c. They correspondingly directthe-fiow of` air when reversed so that it will be directed between said batlies when descending through said stack of lumber so as not to interferewith the ascending streams of heatedair andv steam passing around the sides of said stack.

Vli arrange the ventsy m in the lwalls of the and when the side heat and moisture supplying .elements are actuated and the center elements are turned off, the air Will rise to the side of the pile and descend through the pile to the floor of the kiln and pass along the floor and out through the air outlets, being drawn therethrough by the draft created through the stack into Which the air outlets lead.

The moist air is Warmer than the atmosphere and in passing upward through the vents tends to produce a stack effect, that is, to create a draft through the conduit and thus to draw additional fresh air as before mentioned into the vkiln through the vents f, f and g.

If desirable said conduits may extend entirely through the walls of the dry kiln and open at each end; thus the air can be drawn in throughboth ends of the kiln. ln the latter event, -control devices similar to the valves r r2 and r3, which are hereinafter described, vmust be provided for controlling the flow of air through both ends of said conduits.

bteam is provided from some suitable generator and supplied through the main supply pipe o which branches and supplies steam for the heating coils y', j and through the branch pipes 0, o and 02. The branch pipe 02 has a further branch 03 therefrom which supplies steam to the perforated humidifying pipes z'. Other branch steam pipes 05 and 0G, provided witha common connection, supply steam to the perforated humidifying pipes L and, It", respectively. Each of said pipes are provided with valves 1 p for the heating coil y', p2 for the humidify in g pipes 7L and t, p3 for the heating coils 7c and for the humidifying pipes i, and valve p4 for the heating coils j. Valves are Vprovided for the air conduits f, fv and g also, said valves being respectively marked r, r2 and r3. All of said valves are preferably connected-by a single. pull rod s so that by pushing the rod in o-ne direction all of the valves will `be arranged to cause the circulalion of fluid in one direction in the kiln and by pulling the rod in the opposite direction said circulation will be reversed. This is because the valves r and r2 in the air conduits 7L and it will open with the rod in the position shown in Fig. l, and the valve r3 in the conduit g will be closed. Correspondingly the valves in the heating coils j' and j and it and it are open while the valves in the heating coils 7c and the humidifying pipes z' are closed. This condition will be reversed by moving the pull rod in the opposite direction. As shown inthe figures, the conduit g is twice the size of the conduits 7' or f, or in other words, its capacity is equal to the summation of the capacity of both. Each of the heating coils y' and y" are one-half the sizel of the heating coils lc and the perforated humidifying pipes it and z are single while the pipes z' are double and of the same size. By arranging the devices in this manner an equally eective vcirculation'is arranged by causing the side elements to be actuated to produce circulation in one direction or to cause the middle elements to be actuated to produce circulation in the opposite direction. f

I claim:

l. In a dry kiln, in combination with means for supporting a pilev of material spaced from the floor of the kiln, air-inlets, one located at the middle and one at each .side of the kiln adjacent its fioor, air-outlets located at each side of the kiln under the air-inlets, said air-outlets opening into stacks 1 respectively, partitions separating the airinlet at the middle from those at the sides of the kiln, such partitions extending downward in close proximity to the floor, spray pipes and heating coils associated with each air-inlet whereby exterior air is drawn into, conditioned and induced to circulate through the kiln, and is removed again by the stacks, for replacement by the admission of further eXterior air.

2. In a dry kiln, in combination with means for supporting a pile of material spaced from the floor of the kiln, air-iin lets, one located at the middle and one at each side of the kiln adjacent its floor,` airoutlets located at each sidevof the kiln under the air-inlets, said air-outlets opening into stacks respectively, partitions separating the air-inlet at the middle from those at the sides of [he kiln, such partitions extending downward in close proximity to the Hoor, spray pipes and heating coils associated with each air-inlet and means for controlling each group of air-inlets and the spray pipes and heating coils therewith associa-ted as a unit, thereby to control the direction of the circulated air currents, whereby exterior air is drawn into, conditioned and induced to circulate through the kiln, and

is removed again 'by the stacks, for replace R. A. VsiMMoNs. 

